1. Technical Field
This invention relates to a foldup agricultural implement and more particularly to the hinge connection in the cross axle at the folding axis between a wheeled main frame and a wheeled wing frame.
2. Prior Art Statement
Heretofore others have provided special hinge connections for folding cross axles of wheeled implements which permit the implement wings to be folded 90.degree., more or less, to allow wide implements to be folded to a narrower width for transport purposes. One such construction is shown in U.S. Pat. No. 3,460,631 issued Aug. 12, 1969 to V. W. Friesen et al on a High Clearance Wheel Mounted Spring-Tooth Harrow. When the wing of the Friesen et al construction is folded upwardly to a transport position, the connection between the wing and main frame segments of the cross axle is broken and the wing segment of the cross axle and its wheel are free to swing.
The use of a universal joint in the cross shaft for the transport and/or depth adjusting wheels of a folding implement is shown in the following U.S. patents:
______________________________________ Number Issued Date Inventor and Title ______________________________________ 3,470,965 October 7, 1969 L. R. O. Quickstad; Ground Working Implement With Wing Sections Hinged to Center Section 3,536,144 October 27, 1970 W. R. Hood et al; Articulated Wheeled Frame for Agricultural Implements ______________________________________